Sorry for the vague title. I wasn't sure how to explain it :-).

I just upgraded from verion 1.1 to version 1.2 of MM.NET. After upgrading, I opened the Order System Business Object solution I had built earlier (either version 1.0 or 1.1 of MM.NET). When I tried to open the file Business.cs, I got an error. Something similar to:

The base class 'OakLeaf.MM.Main.Business.mmBusinessObject' cannot be designed.

After awhile, I figured out how to open the file (right-click, Open With..., C Sharp Editor with Encoding). In my file I had:

using OakLeaf.MM.Main;
using OakLeaf.MM.Main.Business;
using OakLeaf.MM.Main.Security;
using OakLeaf.MM.Main.Managers;

namespace Acme.OrderSystem.Business
{
	/// <summary>
	/// Application-level Business Object class
	/// </summary>
	public class ABusinessObject : mmBusinessObject
	{
		public ABusinessObject()
		{
			DatabaseKey = "Northwind";
		}
	}

I changed the definition of the class to:

public class ABusinessObject : OakLeaf.MM.Main.Business.mmBusinessObject

And I was able to open the file normally, no errors like before. Then I changed the definition of the class back to the way it was originally, without the explicit reference:

public class ABusinessObject : mmBusinessObject

And it worked when I tried to open it again normally. Anyone have any idea what's going on?